Does daily aspirin diminish severity of first-ever stroke?

Background: There are still uncertainties about aspirin efficacy in first-ever ischemic stroke prevention. Also it is unknown whether the severity of first ischemic stroke can be modified by aspirin pretreatment. Objective: To analyze a series of patients who had their first ischemic stroke while taking aspirin to evaluate the ability of aspirin prophylaxis to diminish the severity of first-ever ischemic stroke. Design: Case-control study. Setting: Tertiary medical center to which patients were referred. Patients: All consecutive patients admitted to the Tel Aviv Medical Center, Tel Aviv, Israel, from May 1988 through May 1994 because of first-ever ischemic stroke were divided into 2 groups according to aspirin use before stroke: aspirin-treated and non-aspirin-treated groups. Main Outcome Measures: Stroke severity was defined according to activities of daily living within 24 hours after admission: (1) mild stroke, with independence in activities of daily living; (2) moderate stroke, with partial dependency; and (3) severe stroke, with complete dependency. Using chi(2) test, stroke severity was compared between patients taking aspirin before their stroke and non-aspirin-treated patients. Results: Among 2113 consecutive patients with first-ever ischemic stroke, 125 patients had already been taking 100 to 500 mg of aspirin daily. Aspirin-treated and non-aspirin-treated patients did not differ in stroke severity. Mortality was lower in aspirin-treated patients (7.9%) than in non-aspirin-treated patients (12%), but this difference was not statistically significant (P=.17). Conclusions: We conclude that aspirin as primary prevention treatment has no significant protective effect on severity of first-ever ischemic stroke. The diminution of mortality after first ischemic stroke in patients who bad used aspirin should be investigated further.